Requiring territory format validation By default, phone number fields require that a phone number match the display format of the selected territory. By default, phone number fields require that a phone number match the display format of the selected territory. If a phone number does not match this format, the input box displays a red line underneath the phone number and users are prevented from saving it. Figure 1. Phone e164 strict Setting the glide.phone_number_e164.strict system property to false or adding the pn_strict dictionary attribute allows the phone number input box to display a green line underneath numbers that do not match the territory format listed for the selected territory. In this case, a user can save a phone number in an invalid format, but the field continues to display a warning until the phone number matches the format required by the territory. You can use the Other / Unknown territory to store otherwise invalid phone numbers. Figure 2. Phone e164 not strict Warning: Switching from optional territory format validation to required territory format validation may result in some phone numbers failing validation altogether. In such cases, the E.164 phone number field displays an error message.